JP5412794B2 - Polyimide precursor solution composition - Google Patents

Description

  The present invention relates to a polyimide precursor solution composition comprising polyamic acid as a main component. The polyimide precursor solution composition of the present invention is easy to adjust the viscosity of the solution, has a stable solution viscosity, and is equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time. A polyimide resin molded body such as a polyimide film having excellent physical properties can be suitably obtained.

  Polyimide has been widely developed due to its heat resistance and mechanical properties. In particular, wholly aromatic polyimides can exhibit particularly high heat resistance and mechanical properties due to their rigid structure. However, in general, aromatic polyimide is insoluble and infusible, and is often molded using a polyamic acid solution composition that is a precursor thereof. Methods for imidizing polyamic acid include a) heat imidization, b) chemical imidization with a dehydrating agent, and c) combined use of heat imidization and chemical imidization. Among these, the method using chemical imidation of b) and c) can be imidized at a relatively low temperature, but has a problem that it is difficult to obtain a satisfactory polyimide resin molded product because the solution is easily gelled. On the other hand, since the heat imidation of a) involves solvent removal, there is little problem of gelation of the solution. However, in order to obtain a polyimide resin molded body such as a polyimide film having excellent physical properties, high physical properties are required in the heat treatment step. Heat treatment at a high temperature for a long time was necessary, such as stepwise raising the temperature to the maximum heating temperature while applying.

  Patent Document 1 discloses that an aromatic tetracarboxylic acid dianhydride is prepared by using an aromatic tetracarboxylic acid dianhydride in an excess amount of an aromatic diamine so that the acid component and the diamine component are equimolar. A method for improving the physical properties of a polyimide molded product after adjusting the viscosity of the polyamic acid solution and heating imidization by adding carboxylic acid or its anhydride is disclosed. However, the physical properties such as the mechanical properties of the polyimide molded product obtained by this method are not necessarily sufficient, and have physical properties equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time. There was room for improvement in order to suitably obtain a polyimide resin molded body such as a polyimide film.

  Patent Document 2 contains a polyfunctional carboxylic acid compound represented by the following chemical formula, which can form a 3 or 4 imide ring by reacting with an amino group and a polyamic acid having an amino group at the molecular end as a crosslinking component. A varnish is disclosed.

（ここで、ｎは、３または４を、Ｚは３または４価の芳香族基を表す。Ｒ_１、Ｒ_２は、それぞれ独立して、水素、アルキル基またはフェニル基から選ばれる１価の基を表す。）

(Here, n represents 3 or 4, Z represents a trivalent or tetravalent aromatic group. R ₁ and R ₂ are each independently a monovalent group selected from hydrogen, an alkyl group, and a phenyl group. Represents a group.)

However, the polyfunctional carboxylic acid compound represented by the chemical formula in Patent Document 2 is a special compound containing four or more aromatic rings. For this reason, in so-called thermoplastic polyimide having a glass transition temperature of 250 ° C. or lower, it may be effective in improving the solvent resistance, which is a weak point, but the volume of the segment derived from the polyfunctional carboxylic acid compound in the polyimide As the rate increases, it will greatly affect the physical properties such as disturbing the crystallinity of the polyimide, and in particular, in the highly heat-resistant polyimide molded body having a glass transition temperature of 250 ° C. or higher, the original physical properties of the polyimide may be expressed. There was a problem that it was difficult. For this reason, particularly in a high heat-resistant polyimide resin molded body, a polyimide resin molded body such as a polyimide film having physical properties equivalent to or better than linear polyimide is suitably obtained by heat treatment at a relatively low temperature or in a short time. It was difficult.
Further, the polyfunctional carboxylic acid compound is not commercially available and cannot be easily synthesized, so that it is difficult to obtain and very expensive.

JP-A-60-63226 JP 2003-41189 A

  An object of the present invention is to easily adjust the viscosity of a solution, have a stable solution viscosity, and have a physical property equivalent to or better than that of a linear polyimide by heat treatment at a relatively low temperature or in a short time. It is providing the polyimide precursor solution composition which can obtain suitably polyimide resin moldings, such as a film | membrane.

  As a result of various studies, the present inventors have found that a polyimide precursor solution composition in which a merit acid compound having a low molecular weight is added to a polyamic acid solution, the viscosity of the solution can be easily adjusted, the solution viscosity is stable, and It becomes a polyimide resin molded article with high physical properties at a relatively low temperature or short heat treatment stage, and it does not adversely affect physical properties such as the glass transition temperature of polyimide, and is equivalent to or better than linear polyimide. It has been found that a polyimide resin molded body such as a polyimide film having physical properties can be suitably obtained, and the present invention has been achieved.

That is, the present invention relates to the following items.
1. A polyimide precursor solution composition comprising (A) a polyamic acid and (B) a merit acid compound represented by the following chemical formula (1).

［ここで、Ａ^１〜Ａ^６は、それぞれ独立して、水素原子、脂肪族基又は芳香族基から選ばれる１価の基を示す。］

Here, A ^{1 to} A ⁶ each independently represents a monovalent group selected from a hydrogen atom, an aliphatic group, or an aromatic group. ]

2. The molar ratio of the diamine component and the tetracarboxylic acid component constituting the polyamic acid (A) [number of moles of diamine component / number of moles of tetracarboxylic acid component] is in the range of 0.98 to 1.05. Item 2. The polyimide precursor solution composition according to Item 1.

3. Item 1-2 above, wherein the number of moles of merit acid compound (B) is in the range of 0.001 to 0.05 times the number of moles of the diamine component constituting polyamic acid (A). The polyimide precursor solution composition according to any one of the above.

4). The polyimide precursor solution composition according to any one of Items 1 to 3, wherein the polyamic acid (A) has a repeating unit consisting of the following chemical formula (2).

［ここで、Ａは下記化学式（３）で示されたテトラカルボン酸からカルボキシル基を除いた４価の基から選ばれたいずれかの基であり、Ｂは下記化学式（４）で示されたジアミンからアミノ基を除いた２価の基から選ばれたいずれかの基である。］

[Here, A is any group selected from tetravalent groups obtained by removing the carboxyl group from the tetracarboxylic acid represented by the following chemical formula (3), and B is represented by the following chemical formula (4). It is any group selected from divalent groups obtained by removing amino groups from diamines. ]

5. Item 5. The polyimide precursor solution composition according to any one of Items 1 to 4, wherein the solution viscosity at 25 ° C is in the range of 0.1 to 3000 poise.

  According to the present invention, the viscosity of the solution can be easily adjusted, the solution viscosity is stable, and a polyimide film having physical properties equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time The polyimide precursor solution composition which can obtain suitably the polyimide resin molding can be provided.

The merit acid compound used in the present invention is merit acid represented by the chemical formula (1) and its esterified product. That is, as A ^{1 to} A ⁶ in the chemical formula (1), a hydrogen atom at the time of merit acid, and a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a hydroxyethyl group at the time of its esterified product, An aliphatic group such as a methoxyethyl group, preferably an aliphatic group having 1 to 6 carbon atoms or an aliphatic group which may contain an ether bond, an aromatic group such as a phenyl group or a benzyl group, preferably 6 to 12 carbon atoms The aromatic group can be mentioned. Among these, from the viewpoint of ease of handling and availability, merit acid in which all of A ^{1 to} A ⁶ are hydrogen atoms and esterified products having at least a methyl group and an ethyl group are particularly preferable.

Specific compounds include merit acid, merit acid methyl ester, merit acid dimethyl ester, merit acid trimethyl ester, merit acid ethyl ester, merit acid diethyl ester, merit acid triethyl ester, merit acid propyl ester, merit acid dipropyl ester, Preferred examples include merit acid tripropyl ester, merit acid butyl ester, merit acid dibutyl ester, merit acid tributyl ester, merit acid phenyl ester, merit acid diphenyl ester, merit acid triphenyl ester, and the like.
These merit acid compounds can be used alone or in combination. The viscosity of the polyamic acid solution composition becomes unstable when the merit acid compound is dehydrated to contain acid dianhydride groups, acid dianhydride groups, or the like in 5%, particularly 10% or more of the total number of carboxyl groups. It is not preferable because of becoming or gelling.

  The polyamic acid (A) used in the present invention can be suitably obtained by reacting a tetracarboxylic acid component and a diamine component while suppressing imidization. Specific examples of the tetracarboxylic acid component include pyromellitic dianhydride, 4,4′-oxydiphthalic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′. , 4,4′-diphenylsulfonetetracarboxylic dianhydride, 1,1,1,3,3,3-hexafluoropropane-2,2-diphthalic dianhydride, 3,3 ′, 4,4 ′ -Biphenyltetracarboxylic dianhydride, 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 1,2,3 , 4-Benzenetetracarboxylic dianhydride, 3,6-trifluoro-1,2,4,5-benzenetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride 1,4-dimension Toxi-2,3,5,6-benzenetetracarboxylic dianhydride, 1,4-ditrimethylsilyl-2,3,5,6-benzenetetracarboxylic dianhydride, 1,4-bis (3,4 -Dicarboxylphenoxy) benzene dianhydride, 1,3-bis (3,4-dicarboxylphenoxy) benzene dianhydride, 3,3 ', 4,4'-diphenylmethanetetracarboxylic dianhydride, bis (3 , 4-Dicarboxylphenoxy) dimethylsilane dianhydride, bis (3,4-dicarboxylphenoxy) methylamine dianhydride, 4,4′-bis (3,4-dicarboxylphenoxy) biphenyl dianhydride, 4 , 4′-bis (3,4-dicarboxylphenoxy) diphenylsulfone dianhydride, 2,3,5,6-naphthalenetetracarboxylic dianhydride, 2,3,5 6-pyridinetetracarboxylic dianhydride, 2,3,6,7-quinolinetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenyl sulfide tetracarboxylic dianhydride, 3,3,4 , 4'-diphenylsulfoxide tetracarboxylic dianhydride, 1,2,8,9-anthracene tetracarboxylic dianhydride, 1,4-bis (3,4-dicarboxylphenylsulfonyl) benzene dianhydride, 1 , 4-bis (3,4-dicarboxylphenylthio) benzene dianhydride, 3,3 ″, 4,4 ″ -terphenyltetracarboxylic dianhydride, 4-phenylbenzophenone-3,3 ′ ', 4,4 ″ -tetracarboxylic dianhydride, 1,4-bis (3,4-dicarboxylbenzoyl) -benzene dianhydride, 3,3 ′ ″, 4,4 ′ ″-quartylf Nyltetracarboxylic dianhydride, 4,4′-bis (3,4-dicarboxylphenoxy) benzophenone dianhydride, 4,4′-bis (3,4-dicarboxylphenoxy) diphenyl sulfoxide dianhydride, naphthalene Examples thereof include aromatic tetracarboxylic dianhydrides such as tetracarboxylic dianhydride and binaphthalene tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydrides represented by the following chemical formula (5). These aromatic tetracarboxylic dianhydrides may be used alone or in admixture of two or more. Moreover, these aromatic tetracarboxylic dianhydrides can be replaced by derivatives such as esterified products thereof.

（ここで、Ｘは、エステル結合またはエーテル結合を表し、Ｒ_３は、ベンゼン、ナフタレン、ビフェニル、２，２−ビスフェニルプロパン、２，２−ビスフェニルヘキサフルオロプロパン、ジフェニルエーテルからなる２価の芳香族基を表す。）

(Wherein X represents an ester bond or an ether bond, and R ₃ represents a divalent fragrance comprising benzene, naphthalene, biphenyl, 2,2-bisphenylpropane, 2,2-bisphenylhexafluoropropane, and diphenyl ether. Represents a group.)

  Further, a non-aromatic tetracarboxylic acid component may be used. Non-aromatic tetracarboxylic acid components include, for example, butane-1,2,3,4-tetracarboxylic dianhydride, pentane-1,2,4,5-tetracarboxylic dianhydride, cyclobutanetetracarboxylic acid Dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride, cyclohex-1-ene-2,3,5 , 6-tetracarboxylic dianhydride, 3-ethylcyclohex-1-ene-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohexane-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohex-1-ene-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-ethylcyclohexane-1- 1,2), 3,4-tetracarboxylic dianhydride, 1-propylcyclohexane-1- (2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3), 3- (2,3) -tetracarboxylic dianhydride, dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2.2.1] heptane- 2,3,5,6 lacarboxylic dianhydride, 1-propylcyclohexane-1- (2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2, 3), 3- (2,3) -tetracarboxylic dianhydride, dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2.2.1] heptane-2,3 , 5,6-tetracarboxylic dianhydride, bicyclo [ .2.2] octane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride And tetracarboxylic dianhydrides such as These tetracarboxylic dianhydrides may be used alone or in admixture of two or more. Further, these tetracarboxylic dianhydrides can be replaced by derivatives such as esterified products thereof.

  In the present invention, in order to suitably obtain a polyimide resin molded article having physical properties equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time, among these tetracarboxylic acid components, It is preferable to use a derivative such as an aromatic tetracarboxylic dianhydride or an esterified product thereof. Furthermore, considering the availability, ease of handling, excellent heat resistance and mechanical properties, pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2 , 3,3 ′, 4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, or derivatives thereof such as esterified products thereof are preferably used.

  Examples of the diamine component used in the present invention include paraphenylenediamine, 3,3′-dimethyl-4,4′-diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, and 3,3′-. Dimethoxy-4,4′-diaminobiphenyl, 3,3′-dichloro-4,4′-diaminobiphenyl, 9,10-bis (4-aminophenyl) anthracene, 4,4′-diaminobenzophenone, 4,4 ′ -Diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfoxide, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl Sulfone, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxybiphenyl), [4- (4-aminophenoxy) phenyl] ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexafluoro-2,2 -Bis (4-aminophenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,3 , 3,3-hexafluoro-2,2-bis (3-amino-4-methylphenyl) propane, metaphenylenediamine, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfide, 3,4 ′ -Diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) ben 1,4-bis (3-aminophenoxy) benzene, 5-amino-2- (p-aminophenyl) benzoxazole, 6-amino-2- (p-aminophenyl) benzoxazole, 5-amino-2 -(M-aminophenyl) benzoxazole, 6-amino-2- (m-aminophenyl) benzoxazole, toluidinediamine, diaminopolysiloxane, etc. These may be used alone or in combination of two or more. can do.

  In the present invention, an aromatic diamine among these diamine components is preferably used in order to suitably obtain a polyimide resin molded article having physical properties equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time. Is preferably used. Further, in view of easy availability, ease of handling, excellent heat resistance and mechanical properties, it is particularly preferable to use metaphenylene diamine, paraphenylene diamine, 4,4'-diaminodiphenyl ether, toluidine diamine and the like.

  The combination of the tetracarboxylic acid component and the diamine component is not particularly limited, but the glass transition temperature of the polyimide obtained by heat treatment of the polyamic acid obtained from the combination is 250 ° C. or higher, more preferably 255 ° C. or higher. More preferably, it can be 260 ° C or higher, particularly preferably 270 ° C or higher. The glass transition temperature can be suitably measured by methods such as differential scanning calorimetry (DSC), dynamic viscoelasticity measurement, and thermomechanical analysis (TMA).

  That is, in the present invention, the polyamic acid (A) is preferably an aromatic polyamic acid composed of an aromatic tetracarboxylic acid component and an aromatic diamine component, and more preferably a polyimide obtained by heat-treating the polyamic acid. The glass transition temperature of the resin is such that it can be 250 ° C. or higher, more preferably 255 ° C. or higher, more preferably 260 ° C. or higher, particularly preferably 270 ° C. or higher. It is.

  There is no restriction | limiting in the preparation method of the polyamic acid used for this invention, A well-known method can be used suitably. For example, tetracarboxylic dianhydride and diamine are preferably reacted in an organic solvent for 0.5 to 78 hours in an inert atmosphere at a concentration such that the polyamic acid concentration is 5 to 60% by mass. Can get to. In this case, for example, a) acid dianhydride is added to a solution in which diamine is dissolved at a time or divided into several times for reaction, and b) diamine and acid dianhydride are added to the solvent at a time for reaction. ) A diamine and an acid dianhydride can be suitably prepared by adding them in several portions and reacting them. The reaction temperature should just be a temperature range which can suppress imidation reaction, Preferably it is 5-80 degreeC, More preferably, it is 10-70 degreeC, More preferably, it is a temperature range of 10-65 degreeC. If it is lower than 5 ° C., the reaction is delayed and takes a long time. If it is higher than 80 ° C., the imidization reaction may proceed to cause precipitation, which is not preferable.

  As the organic solvent used for the preparation of the polyamic acid, known solvents used for the preparation of the polyamic acid can be preferably used. For example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethyl Acetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, hexamethylphosphorotriamide, 1,2-dimethoxyethane, bis ( 2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, tetrahydrofuran, bis [2- (2-methoxyethoxy) ethyl] ether, 1,4-dioxane, dimethyl sulfoxide, dimethyl sulfone, diphenyl ether, Sulfolane, diphenylsulfone, tetramethylurine , Such as anisole, and the like. These solvents may be used alone or in combination of two or more.

The molar ratio [number of moles of diamine component / number of moles of tetracarboxylic acid component] of the diamine component and the tetracarboxylic acid component constituting the polyamic acid of the present invention is 0.98 to 1.05, preferably 0.985. The range is 1.045, more preferably 0.985 to 0.999 or 1.001 to 1.040, and still more preferably 0.990 to 0.999 or 1.001 to 1.040. Outside this range, the increase in the molecular weight of the polyimide during the heat treatment is not sufficient, and the physical properties of the resulting polyimide resin molded article may be lowered, which is not preferable.
The polyamic acid of the present invention preferably has a logarithmic viscosity (concentration of 0.5 g / 100 ml, 30 ° C. in N-methyl-2-pyrrolidone solvent) of 0.01 to 4.

The polyimide precursor solution composition of the present invention is obtained by adding the merit acid compound (B) to the polyamic acid (A) solution prepared as described above, and stirring and dissolving as necessary at a relatively low temperature, preferably at normal temperature. By doing so, it can be suitably obtained.
The polyamic acid solution used for preparing the polyimide precursor solution composition may be the prepared polyamic acid solution as it is, or the polyamic acid isolated by removing the organic solvent is dissolved again in the organic solvent. May be used.

  The concentration of the polyamic acid (A) solution used when preparing the polyimide precursor solution composition is 3 to 60% by mass, preferably 5 to 50% by mass, more preferably 5 to 40% by mass, and still more preferably 5 to 5% by mass. It is in the range of 35% by mass. If the concentration is less than 5% by mass, the amount of the organic solvent to be removed by heat treatment increases, which is not preferable. On the other hand, if it exceeds 60% by mass, the viscosity of the solution increases and molding becomes difficult. Moreover, the above-mentioned organic solvent used for preparation of a polyamic acid can be used suitably as an organic solvent.

  The addition amount of the merit acid compound is 0.001 to 0.05 times mol, more preferably 0.001 to 0.04 times mol, when the number of moles of the diamine component constituting the polyamic acid (A) is 1. More preferably, it is in the range of 0.0015 to 0.03 moles. If the addition amount is less than 0.001 mol, it is difficult to obtain the effect of the present invention. On the other hand, if the addition amount is more than 0.05 mol, the physical properties of the resulting polyimide resin molded product may be deteriorated.

  In the polyimide precursor solution composition of this invention, you may add the poor solvent of a polyamic acid in the range which does not impair solubility other than the solvent which can be used suitably for preparation of the said polyamic acid (A). Specific examples of the poor solvent include xylene, ethyl cellosolve, diglyme, dioxane, methanol, ethanol, n-propanol, iso-propanol, n-butanol and sec-butanol. , N-amyl alcohol, n-hexanol, n-heptanol and the like.

  The polyimide precursor solution composition of the present invention can be easily adjusted in viscosity such as lowering viscosity or increased in concentration. Furthermore, a polyimide resin molded body such as a polyimide film having a stable property viscosity and a physical property equivalent to or superior to that of linear polyimide can be suitably obtained by heat treatment at a relatively low temperature or in a short time. . As the heat treatment method, a known method for obtaining a normal polyimide can be used. For example, after applying and casting a polyimide precursor solution composition on a substrate, the obtained coating film is subjected to, for example, a hot air dryer. After removing the solvent by heat treatment at a relatively low temperature using a polyimide resin molded body (polyimide film) as it is or after peeling from the substrate as necessary, and heat treatment at a higher temperature It can be. At this time, the maximum temperature of the heat treatment is preferably in the range of 180 to 500 ° C, more preferably 190 to 480 ° C, still more preferably 200 to 470 ° C, and particularly preferably 210 to 460 ° C. When the maximum temperature of the heat treatment is lower than 180 ° C., it is not preferable because it requires a long time for imidization, and the physical properties of the polyimide resin molded article are lowered. On the other hand, when the temperature exceeds 500 ° C., the thermal decomposition of the polyimide resin is not preferable. This is not preferable because it may progress and cause a decrease in physical properties.

  The polyimide precursor solution composition of the present invention is not limited, but the polyamic acid concentration is 3 to 60% by mass, preferably 5 to 50% by mass, more preferably 5 to 35% by mass, and the solution viscosity. Although it does not limit, it is 0.1-3000 poise in 25 degreeC, Preferably it is 0.1-1000 poise, More preferably, it is 0.5-500 poise, Most preferably, it is 1-200 poise. Further, the polyimide precursor solution composition of the present invention may suitably contain an organic or inorganic additive such as a filler, a filler, a reinforcing material, a pigment, a dye, a release agent, etc., depending on the application. it can.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, it is not limited to these Examples. A method for measuring the characteristics used in the examples is shown below.

<Solution viscosity>
The solution viscosity of the polyamic acid solution composition or the polyimide precursor solution composition was measured at 25 ° C. using an E-type viscometer.

<Mechanical properties (tensile test)>
The tensile test was performed by pulling a dumbbell-shaped test piece at a speed of 5 mm / min using EZTset manufactured by Shimadzu Corporation in an atmosphere of 25 ° C. and 50% RH. The elastic modulus, elongation at break, and strength at break were determined from the tensile break data. The test piece used was a distance between gauge points of 26.32 mm and a width of 4 mm. About each sample, it measured so that n number might be set to 5 or more, and calculated | required the arithmetic mean.

[Example 1]
Dissolve 20.02 g (0.100 mol) of 4,4′-diaminodiphenyl ether (hereinafter also abbreviated as ODA) in 221 g of N-methyl-2-pyrrolidone (hereinafter also abbreviated as NMP). 28.54 g (0.097 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (hereinafter sometimes abbreviated as BPDA) was added to the solution, and BPDA was added at 25 ° C. Was dissolved for 24 hours until it became a viscous solution to obtain a polyamic acid solution. The polyamic acid concentration of this solution was 18% by mass, and the viscosity was 41 poise. To this solution, 0.68 g (0.002 mol, 0.02 mol per mol of ODA) of merit acid was added to prepare a polyamic acid solution composition. The viscosity of the obtained polyimide precursor solution composition was 41 poise, and hardly changed even when stored for 3 days at room temperature.
The obtained polyimide precursor solution composition was cast on a glass plate and dried with hot air at 120 ° C. for 30 minutes. Furthermore, after peeling from the glass plate, it was fixed to a metal frame and heated at 250 ° C. for 10 minutes to obtain a polyimide film having a thickness of 40 μm. Furthermore, the polyimide film which heated the polyimide film for 10 minutes at 350 degreeC was also obtained. The properties of the obtained polyimide film are shown in Table 1.

[Comparative Example 1]
Instead of adding merit acid, instead of adding 1.10 g (0.003 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic acid (hereinafter sometimes abbreviated as BPTA), A polyimide precursor solution composition was prepared in the same manner as in Example 1. The ratio of the carboxylic acid group of BPTA to the amine component at this time is the same as the ratio of the carboxylic acid group of merit acid to the amine component of Example 1.
A polyimide film was obtained in the same manner as Example 1 using the obtained polyimide precursor solution composition. The properties of the obtained polyimide film are shown in Table 1.

The polyimide obtained in Comparative Example 1 is a linear polyimide obtained by making the tetracarboxylic acid component and the diamine component of the polyamic acid (A) used in Example 1 substantially equimolar.
The physical properties of the polyimide film of Example 1 were particularly high when heated at a low temperature as compared with Comparative Example 1, and even when heat-treated at 350 ° C., the physical properties were equal to or higher than those of Comparative Example 1.

  According to the present invention, the viscosity of the solution can be easily adjusted, the solution viscosity is stable, and a polyimide film having physical properties equivalent to or better than linear polyimide by heat treatment at a relatively low temperature or in a short time The polyimide precursor solution composition which can obtain suitably the polyimide resin molding can be provided.

Claims (3)

(A) a polyamide acid, viewed contains a trimellitic acid compound represented by (B) the following chemical formula (1), the molar ratio of the diamine component and the tetracarboxylic acid component constituting the polyamic acid [diamine component / mole number tetra The number of moles of the carboxylic acid component] is in the range of 1.001 to 1.05, and the number of moles of the merit acid compound is 0.001 to 0.05 times the mole of the diamine component constituting the polyamic acid. A polyimide precursor solution composition characterized by being in the range of

Here, A ^{1 to} A ⁶ each independently represents a monovalent group selected from a hydrogen atom, an aliphatic group, or an aromatic group. ] Polyamic acid (A) is a polyimide precursor solution composition according to claim 1, characterized in that it comprises a repeating unit consisting of the following chemical formula (2).

[Here, A is any group selected from tetravalent groups obtained by removing the carboxyl group from the tetracarboxylic acid represented by the following chemical formula (3), and B is represented by the following chemical formula (4). It is any group selected from divalent groups obtained by removing amino groups from diamines. ]

Solution viscosity at 25 ° C., a polyimide precursor solution composition according to any one of claims 1-2, characterized in that in the range of from 0.1 to 3000 poise.